| 摘要 |
PROBLEM TO BE SOLVED: To provide an objective lens whose structure is very simple, which is made small and light though it is equipped with a heat radiation mechanism, and which is made immune to vibration and shock from the outside and very reliable as an objective lens for optical pickup capable of realizing high recording density. SOLUTION: As for this objective lens 1 equipped with a plurality of lens parts 3 and 4 and having high NA, heat generated from a spot on an optical disk 2 is radiated to the air from a radiation fin 6 formed on the opposed surface side of the disk 2 even when it is transmitted to the lens 1, so that the temperature rise of the lens 1 is restrained. Furthermore, since the structure of the lens 1 is very simple, the lens 1 is made small and light. |
